Fuel Pump (FP) Control Module, Checking

Fuel Pump (FP) Control Module, Checking

Recommended special tools and equipment
- V.A.G 1526 multimeter or V.A.G 1715 multimeter
- V.A.G 1594 connector test kit
- Wiring diagram

Test requirements







- Corresponding fuses on fuse holder in instrument panel, right side, for Fuel Pump (FP) Control Module -J538- must be OK.

NOTE: Fuses on this fuse holder are labelled "SD" in the wiring diagram.

- Battery voltage must be at least 11.5 Volts.
- All electrical consumers such as, for example, lights and rear window defroster must be switched off.
- Ground (GND) connections between engine and chassis must be OK.
- Ignition switched off.

Test sequence
Observe safety precautions.
Observe rules for cleanliness.

- Remove seat bench.







- Disconnect 10-pin connector -arrow- from Fuel Pump (FP) Control Module -J538-.

Checking voltage supply







- Connect multimeter with test leads to terminals 1 and 6 of connector for voltage measurement (terminal 30).

Specified value: at least 11.5 V

If specified value is not obtained:
- Locate and repair open circuit using wiring diagram.
- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data. Diagnostic Mode 04 - Erase DTC Memory
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes

If specified value is obtained:







- Connect multimeter with test leads to terminals 3 and 6 of connector for voltage measurement (terminal 15).
- Switch ignition on.

Specified value: at least 11.5 V

- Switch ignition off.

If specified value is not obtained:
- Locate and repair open circuit using wiring diagram.
- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data. Diagnostic Mode 04 - Erase DTC Memory
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes

If there is no malfunction in voltage supply:
- Check wire to Engine Control Module (ECM) according to wiring diagram.

Checking wire to Engine Control Module (ECM)
- Connect test box to 94-pin connector of wiring harness, connecting test box for wiring test.

Engine Control Module (ECM) is not connected.







- Check wire between test box and 10-pin connector to Engine Control Module (ECM) for open circuit according to wiring diagram.
Terminal 2 + socket 27

Wire resistance: max. 3.0 ohms

- Also check the wire for short circuit to B+ and to Ground (GND).

Specified value: infinity ohms

- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data. Diagnostic Mode 04 - Erase DTC Memory
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes

If no malfunction is detected in the wire and the voltage supply was OK:
- Replace Fuel Pump (FP) Control Module -J538-.
- Erase DTC memory of Engine Control Module (ECM), Diagnostic mode 4: Reset/erase diagnostic data. Diagnostic Mode 04 - Erase DTC Memory
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes